Reaction of chemisorbed CH and H on nickel

Journal Article · Sat Jul 01 04:00:00 EDT 1989 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.457499· OSTI ID:6262881

Yang, H; Whitten, J L

The reaction of chemisorbed CH and H on the (111) surface of Ni is treatedusing a many-electron embedding theory to describe the electronic bonding, modelling the lattice as a 28-atom, three layer cluster. /ital Ab//nitio/ valence orbital CI calculations carried out on a local surface region permit an accurate description of bonding at the surface. Both CH and CH/sub 2/ species are found to bind strongly to the Ni(111) surface at threefold and bridge sites. Adsorption energies are between 2.9 and 3.1 eV forCH adsorption, and 2.5 and 2.9 eV for CH/sub 2/ adsorption. Atop Ni adsorption sites are more than 1 eV higher in energy. The Ni--C bond lengths range from 2.00 to2.04 A for CH and CH/sub 2/ on the surface. Vibrational frequencies for HC-surface and H/sub 2/C-surface vibrations are between 400 and 600 cm/sup /minus/1/; CHstretching frequencies are around 3050 cm/sup /minus/1/ in both CH and CH/sub 2/. There action of CH+H/r arrow/CH/sub 2/ on the nickel surface is 1.45 eV exothermic, however, a barrier exists to moving H to a threefold site adjacent to one occupied by CH. The geometries of CH and CH/sub 2/ and the nature of the bonding to the surface are discussed.

• Research Organization: Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794-3400(US)
• OSTI ID: 6262881
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 91:1; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
BOND LENGTHS
CHEMICAL BONDS
CHEMICAL REACTIONS
CHEMISORPTION
CONFIGURATION INTERACTION
DIMENSIONS
ELEMENTS
HYDROGEN
LENGTH
METALS
METHYLENE RADICALS
NICKEL
NONMETALS
RADICALS
SEPARATION PROCESSES
SORPTION
SORPTIVE PROPERTIES
SURFACE PROPERTIES
TRANSITION ELEMENTS